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This study aimed to assess whether standard-dose Betahistine (48 mg daily) exerts an effect upon the degree of endolymphatic hydrops in patients with Menière's disease using a retrospective case series in the setting of a tertiary neurotology referral centre. In six patients with definite unilateral Menière's disease, the degree of cochlear and vestibular endolymphatic hydrops was assessed before and after treatment with a standard dose of Betahistine (48 mg daily), using high-resolution 3 T MR imaging after intratympanic contrast medium application. The treatment duration was 3-7 months (mean 5 months), and the patients were followed-up for 6-29 months (mean 11 months). In the study cohort, the standard dose of Betahistine did not have an MR morphologically measurable beneficial effect on the degree of endolymphatic hydrops. The results indicated no effect of standard-dose Betahistine on endolymphatic hydrops found on high-resolution MR imaging. Possible explanations are: (1) insufficient dosage or duration of treatment with betahistine, (2) insufficient resolution of the MR imaging technique, and (3) insufficient length of follow-up. Further studies addressing these issues are warranted.

Standing, walking, and running are sensorimotor tasks that develop during childhood. Thereafter they function automatically as a result of a supraspinal network that controls spinal pattern generators. The present study used functional magnetic resonance imaging (fMRI) to investigate age-dependent changes in the supraspinal locomotor and postural network of normal subjects during mental imagery of locomotion and stance. Sixty healthy subjects (ages: 24-78 years), who had undergone a complete neurological, neuro-ophthalmological, and sensory examination to rule out disorders of balance and gait, were trained for the conditions lying, standing, walking, and running in order to imagine these conditions on command in 20-second sequences with the eyes closed while lying supine in an magnetic resonance imaging (MRI) scanner. The following blood oxygen level-dependent (BOLD) signal changes during locomotion and stance were found to be independent of age: (1) prominent activations in the supplementary motor areas, the caudate nuclei, visual cortical areas, vermal, and paravermal cerebellum; (2) significant deactivations in the multisensory vestibular cortical areas (posterior insula, parietoinsular vestibular gyrus, superior temporal gyrus), and the anterior cingulate during locomotion. The following differences in brain activation during locomotion and stance were age-dependent: relative increases in the cortical BOLD signals in the multisensory vestibular cortices, motion-sensitive visual cortices (MT/V5), and somatosensory cortices (right postcentral gyrus). In advanced age this multisensory activation was most prominent during standing, less during walking, and least during running. In conclusion, the functional activation of the basic locomotor and postural network, which includes the prefrontal cortex, basal ganglia, brainstem, and cerebellar locomotor centers, is preserved in the elderly. Two major age-dependent aspects of brain activation during locomotion and stance were found: the mechanism of cortical inhibitory reciprocal interaction between sensory systems during locomotion and stance declines in advanced age; and consequently, multisensory cortical control of locomotion and stance increases with age. These findings may indicate a more conscious locomotor and postural strategy in the elderly., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Our objective is to determine whether the degree of endolymphatic hydrops as it is detected in vivo in patients with definite Meniere's disease correlates with audiovestibular function. In this prospective study, 37 patients with definite Meniere's disease according to AAO-HNS criteria were included. Intratympanic contrast enhanced temporal bone MRI was performed using a 3D FLAIR protocol. The degree of endolymphatic hydrops in the cochlea and the vestibulum was graded on a Likert scale (0-3). The degree of hydrops was then analyzed with respect to its correlation with audiometric hearing levels, electrocochleographic SP/AP ratios, interaural amplitude ratios of vestibular evoked myogenic potentials and degree of horizontal semicircular canal paresis on caloric irrigation. There was a significant correlation between the degree of hydrops on the one hand and the averaged hearing level at 0.25-1 and 0.5-3 kHz and the vestibular evoked myogenic potential interaural amplitude ratio on the other hand. A trend toward a correlation was noticed between the hydrops and the caloric response, no correlation was noticed between the hydrops and the SP/AP ratio. The degree of endolymphatic hydrops correlates with a progressive loss of auditory and sacculus function in patients with Meniere`s disease.

The cortical, cerebellar and brainstem BOLD-signal changes have been identified with fMRI in humans during mental imagery of walking. In this study the whole brain activation and deactivation pattern during real locomotion was investigated by [(18)F]-FDG-PET and compared to BOLD-signal changes during imagined locomotion in the same subjects using fMRI. Sixteen healthy subjects were scanned at locomotion and rest with [(18)F]-FDG-PET. In the locomotion paradigm subjects walked at constant velocity for 10 min. Then [(18)F]-FDG was injected intravenously while subjects continued walking for another 10 min. For comparison fMRI was performed in the same subjects during imagined walking. During real and imagined locomotion a basic locomotion network including activations in the frontal cortex, cerebellum, pontomesencephalic tegmentum, parahippocampal, fusiform and occipital gyri, and deactivations in the multisensory vestibular cortices (esp. superior temporal gyrus, inferior parietal lobule) was shown. As a difference, the primary motor and somatosensory cortices were activated during real locomotion as distinct to the supplementary motor cortex and basal ganglia during imagined locomotion. Activations of the brainstem locomotor centers were more prominent in imagined locomotion. In conclusion, basic activation and deactivation patterns of real locomotion correspond to that of imagined locomotion. The differences may be due to distinct patterns of locomotion tested. Contrary to constant velocity real locomotion (10 min) in [(18)F]-FDG-PET, mental imagery of locomotion over repeated 20-s periods includes gait initiation and velocity changes. Real steady-state locomotion seems to use a direct pathway via the primary motor cortex, whereas imagined modulatory locomotion an indirect pathway via a supplementary motor cortex and basal ganglia loop., (2009 Elsevier Inc. All rights reserved.)

The hippocampal formation, including the parahippocampal gyrus, is known to be involved in different aspects of navigation and spatial orientation. Recently, bilateral parahippocampal activation during mental imagery of walking and running was demonstrated in fMRI. For the current study the question was whether distinct functional regions within the hippocampal formation could be defined from the analysis of brain activity during imagery of stance and locomotion in healthy, blind, and vestibular-loss subjects. Using the same experimental paradigm in all groups (fMRI during mental imagery of stance and locomotion after training of actual performance, regions of interest [ROI] analysis), activations were found in the hippocampal formation, predominantly on the right side, in all subjects. In healthy subjects, standing was associated with anterior hippocampal activation; during locomotion widespread activity was found in the right parahippocampal gyrus. Compared to healthy controls, blind subjects showed less activity in the right dorsal parahippocampal region, whereas vestibular-loss subjects had less activity in the anterior hippocampal formation. The findings show that the hippocampal formation in humans processes visual and vestibular signals in different regions. The data support the assumption that the anterior hippocampus and the entorhinal cortex in the parahippocampal region are input areas for vestibular and somatosensory signals. Posterior parahippocampal and fusiform gyri, which are connected to visual cortical areas, are more important for visually guided locomotion and landmark recognition during navigation. The right-sided dominance reflects the importance of the right hemisphere for spatial orientation.

Functional magnetic resonance imaging (fMRI) in sighted individuals previously showed parahippocampal and fusiform activations during locomotor imagery, which were interpreted to reflect visuospatial navigation. Concurrent deactivations of multisensory vestibular and somatosensory cortical areas may reflect suppression of vestibular and somatosensory input, in order to prevent adverse interactions of sensory signals with the optimized automated locomotion pattern. In this fMRI study we compared blood oxygen level dependent (BOLD) activations and deactivations during the kinesthetic imagery of standing, walking, and running in seven congenitally totally blind subjects, seven sighted age-matched controls, and five subjects with age at onset of complete blindness > or =9 y or minimal residual vision. Imagined lying served as the rest condition. As opposed to their sighted controls, congenitally totally blind individuals activated multisensory vestibular areas in the posterior insula and superior temporal gyrus during imagined locomotion. Further, congenitally blind individuals did not show activations in parahippocampal and fusiform regions during locomotor tasks. In the intergroup comparisons, congenitally blind subjects exhibited higher BOLD activity levels than sighted subjects in multisensory vestibular (posterior insula and adjacent temporal sites), somatosensory (postcentral gyrus), and primary motor cortical areas, while sighted subjects showed higher activity levels in the parahippocampal and fusiform gyri. These findings indicate that blind subjects rely more on vestibular and somatosensory feedback for locomotion control than sighted subjects. This is accompanied by enhanced voluntary motor control and enhanced motor-kinesthetic processing. Thus, we provide neuroimaging evidence of distinct sensorimotor strategies in the blind for locomotor control.

The authors evaluated floccular activity with fMRI during the performance of vertical smooth pursuit eye movements in four patients with downbeat nystagmus (DBN) due to cerebellar degeneration and in 16 healthy controls. Region of interest analysis revealed a significantly diminished activation of both floccular lobes during downward but not upward pursuit in DBN. These imaging data support the view that a functional deficiency of the flocculi in downward pursuit causes DBN.

Posture and gait are sensorimotor actions that involve peripheral, spinal, and supraspinal structures. To investigate brain activity during stance and locomotion, 13 healthy subjects were asked to stand, walk, run, and lie down; subsequently, they were trained to imagine standing, walking, running, and lying [imagined lying as rest condition in functional magnetic resonance imaging (fMRI)]. Separate and distinct activation/deactivation patterns were found for the three imagined conditions: (1) standing imagery was associated with activation in the thalamus, basal ganglia, and cerebellar vermis; (2) walking imagery was associated with activation in the parahippocampal and fusiform gyri (areas involved in visuospatial navigation), occipital visual areas, and in the cerebellum; (3) running imagery caused a predominantly cerebellar activation in the vermis and adjacent hemispheres (six times larger than during imagination of walking or standing), but activations in the parahippocampal and fusiform gyri were smaller than during walking. Deactivations were found for walking and running, but not for standing imagery. They were located in the vestibular (posterior insula, superior temporal gyrus, supramarginal gyrus) and somatosensory (postcentral gyrus) cortex with right-hemispheric dominance. These findings support the concept of a hierarchical organization of posture and locomotion. Automated locomotion, for example, running, is based on spinal generators whose pace is driven by the cerebellar locomotor region. Deactivation in the vestibular and somatosensory cortex prevents adverse interactions with the optimized spinal pattern and sensory signals; this confirms earlier findings of a multisensory inhibition during unhindered locomotion. During slow walking, spatial navigation, mediated by the parahippocampal cortex, becomes more important. Postural control during standing involves a low intensity cerebellar activity and sensorimotor control via the thalamus and basal ganglia.

Prompted by the findings of previous studies with positron emission tomography and single photon emission computed tomography, which demonstrated hypoperfusion or hyperperfusion in the left temporal lobe in isolated patients with transient global amnesia (TGA), we compared the sensitivity of diffusion-weighted (DW) magnetic resonance imaging (MRI) with that of conventional T1- and T2-weighted MRI in patients with TGA. Ten patients with the typical syndrome of a pure TGA were included in the study. For all patients, a coronal DW sequence, a steady-state free precession (SSFP) sequence, and conventional T1- and T2-weighted turbo spin-echo sequences were obtained. Seven of the 10 patients had elevated signal intensity in the left hippocampal region on DW MRI; moreover, 3 of these 7 patients exhibited bilateral signal abnormality in this sequence. All conventional T1- and T2-weighted images as well as all follow-up studies were normal. The signal elevation in DW MRI correlates with a decrease in the interstitial space and with cellular edema in the temporal lobe during TGA. The underlying pathomechanism causing this cellular edema cannot be clearly outlined using DW MRI. Our data are, however, compatible with spreading depression. This is the first study to show that DW MRI is a sensitive MRI method for evaluating TGA, especially in the early stage of the disease.

High resolution magnetic resonance imaging (HR-MRI) and computed tomography (HR-CT) of the inner ear are becoming more important for the diagnosis of peripheral vestibular lesions. Modern HR-MRI techniques allow visualization of detailed anatomic features of the vestibulo-cochlear regions as well as pathologic findings in the inner ear such as, neoplastic lesions (e.g., small intracanalicular acoustic neuromas), anomalies causing vertigo and hearing loss (e.g. Mondini's-malformation, perilymph fistula, vestibular paroxysmia), and inflammatory diseases (e.g., Cogan's syndrome, labyrinthitis, zoster neuritis). HR-CT is still the first examination that should be performed in patients with middle ear diseases (e.g., tumor, infection), trauma (e.g. temporal bone fractures), or fibro-osseous diseases. Although the imaging of the vestibulo-cochlear system has dramatically improved, there are still several peripheral vestibular disorders that cannot be visualized so far, e.g., benign paroxysmal positioning vertigo, idopathic vestibular neuritis or Menière's disease.

A patient is reported on with a common variable immunodeficiency syndrome (CVID), in whom chronic gastritis with antibodies against parietal cells and a cytomegalovirus associated enteritis led to vitamin B12 deficiency with consecutive subacute combined degeneration of the spinal cord. The resulting medullary changes, most probably representing demyelination, were visualised with MRI. The effects of treatment were also monitored over three years by MRI and clinical examination. The resolution of the MRI changes correlated with clinical improvement of the patient's signs. In the medical literature only five cases of vitamin B12 related spinal cord changes have been identified by MRI; none was caused by a CVID syndrome. [ABSTRACT FROM AUTHOR]

The article discusses case of a 45 year old woman suffering with the attacks of vertigo induced by changing of body position. Magnetic resonance imaging (MRI) revealed a cystic lesion in the right cerebellar vermis. The patient was treated with four-aminopyridine which treated the symptoms in three days and it was also beneficial in preventing attacks of episodic ataxia type.

The article presents several research works related to multiple sclerosis (MS). According to a research concerned with brain iron mapping in MS by magnetic resonance imaging (MRI), high levels of iron lead to brain damage, primarily because of the toxic effects by increased production of free radicals. According to a research concerned with the analysis of teriflunomide for its use in treating MS, disease activity is significantly reduced with the use of teriflunomide.

Abstract: In functional brain imaging, specific task conditions can be compared to a reference condition which is often eyes-open or eyes-closed in darkness without the execution of a specific task. Previous fMRI studies in sighted subjects have shown that eyes-open in darkness, without visual stimulation, increases the relative activity in cortical ocular motor and attentional areas (“exteroceptive” state; contrast OPEN>CLOSED). By contrast, eyes-closed causes a relative signal increase in sensory systems (“interoceptive” state; contrast CLOSED>OPEN). In the present study we used fMRI to determine whether these differential brain activity states can also be found in congenitally blind subjects: there were intragroup differences between the OPEN and CLOSED conditions. These differences were, however, less pronounced and occurred in other areas than in sighted controls. The contrast OPEN>CLOSED revealed a relative signal increase in the left frontal eye field, the middle occipital gyrus bilaterally and in the anterior cingulum. Relative signal increases in occipital cortex areas and the anterior cingulum were also apparent for this contrast in the intergroup comparison (congenitally totally blind subjects vs. sighted controls). They reflect the increased attentional load or arousal during the eyes-open condition and could be indicative of a functional reorganization of the occipital cortex in the blind. The contrast CLOSED>OPEN in the congenitally totally blind subjects lead to relative activations in the somatosensory cortex bilaterally, the middle temporal gyrus on the left and the frontal gyri on the right. These activations are residues of the “interoceptive” state found in sighted controls. [Copyright &y& Elsevier]